From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?UTF-8?Q?Court=C3=A8s?=)
Subject: bug#22354: Hash-bang line length
Date: Wed, 13 Jan 2016 14:52:08 +0100
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References: <87lh7t7p4w.fsf@gnu.org> <20160113131902.GU27325@eeg.ccf.org>
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To: Greg Wooledge <wooledg@eeg.ccf.org>
Cc: 22354@debbugs.gnu.org, bug-bash@gnu.org

Greg Wooledge <wooledg@eeg.ccf.org> skribis:

> On Wed, Jan 13, 2016 at 11:25:03AM +0100, Ludovic Court=C3=A8s wrote:
>> Hello,
>>=20
>> The ???READ_SAMPLE_BUF??? macro in execute_cmd.c reads at most 80 bytes =
from
>> the hash-bang line.  This is less than the already-small 128-byte limit
>> in the Linux kernel=C2=B9 and can quite easily be hit=C2=B2.
>
> That's actually much bigger than one expects for shebang handling on
> any traditional Unix system.

Sure, but the fact that it=E2=80=99s smaller than that of the kernel Linux =
is
problematic: when a hash-bang line > 127 chars is encountered, =E2=80=98exe=
cve=E2=80=99
fails with ENOENT, so Bash=E2=80=99s fallback code is executed, fails as we=
ll,
but it prints a misleading error message with an even more truncated
hash-bang line.

Ludo=E2=80=99.